The specific objectives of the Pathology and Tissue Procurement Core are to: Provide a centralized resource dedicated to procurement and processing of tumor tissue for translational research from nearly every patient with newly diagnosed or relapsed primary central nervous system tumors receiving care at the Mayo Clinic, Rochester, MN. - Coordinate acquisition and timely distribution of brain tumor tissue in excess of clinical diagnosis, ensuring appropriate diagnosis and quality of tissue. A portion of fresh tumoral brain tissue and normal tissue (when available) from each patient will be obtained fresh, processed for culture/xenografting and/or stored frozen to provide investigators with DNA and RNA. The remainder of the tissue will be available in paraffin blocks stored at the Mayo Clinic Tissue Registry. Provide a comprehensive histologic characterization of all tissue samples used in the individual SPORE Projects, including specimens from patients and experimental tumors in animals, as well as provide expertise in the interpretation of studies performed on paraffin embedded and/or frozen tissue sections. - Offer comprehensive services, including immunohistochemical characterization of biomarkers, tissue microarray design and construction, and DNA or RNA extraction. - Maintain and enhance a repository of tumor tissue and matched blood specimens in conjunction with the Clinical Research Core. The Core will interface with and be electronically integrated with the Clinical Research and the Biostatistics Cores to provide investigators with clinically annotated tissues. The collection, banking, and use of tissue will be performed with appropriate patient consent and institutional approval. - Promote and facilitate sharing of tissue resources with other Brain Tumor SPOREs through collaborative scientific projects of mutual interest.